What do you use to measure Phosphate?

[Bidadari]

I'm wondering if anyone use a better measuring test to measure phosphate level in their tank, especially SPS tank.
I have one of those Salifert test, but I hate color comparison test since it's so easy to get unaccurate result depending on how good your eyes is with color, and color changes too with light.
I did some search & come up with this
http://www.hannainst.com/products/ion/photometers.cfm?ProdCode=HI 93713

 

[JayG]

Expensive but a very good kit

http://www.deltecusa.us/aquariummedia/phosphatetestkit.php

"It is the only phosphate test kit able to take accurate readings from a minimum level of 0.00 to a max level of 0.14 PO4"

 

[Triggerfish]

are there any specific reasons you want to test for PO4 beyond to make sure you are not adding any into your system via source water? if not, then that unit may not be good enough due to:

Accuracy (@20?C/68?F) ?0.04 mg/L ?4% of reading

 

[Bidadari]

Do you know how it works? Does it gives a digital reading?
It looks pretty good, still cheaper than the one I found (Hanna Instrument)

 

[Randy Holmes-Farley]

I like the Hach phosphate kit, PO-19

www.hach.com

 

[Bidadari]

are there any specific reasons you want to test for PO4 beyond to make sure you are not adding any into your system via source water? if not, then that unit may not be good enough due to:

Accuracy (@20?C/68?F) ?0.04 mg/L ?4% of reading

I'm really curious to know the phosphate level in my tank. I have a few acro that was very colorful when I bought it, but now it changes to light tan color, so I'm wondering if my tank phosphate level contributes to the color changes.

 

[Greg Hiller]

Randy,

Every time I've ever run the Hach kit I always get a value of 0.06 mg/l, which is just at the limit of detection. But I though everyone says you should try for a lower level. Have you been able to accurately measure below 0.06?